如何用PHP获取无字段的json数据

class CcAction extends Action {
 public function getjson(){
 echo json_encode($GLOBALS['HTTP_RAW_POST_DATA']);//这里就能获取到testcurl传来的$json_string
 }
 public function testcurl(){
 $header = array('Accept:application/json', 'Content-Type:application/json');
 $patoken = array(
 'name' => 'phpjyz',
 'age' => '23',
 );
 $json_string = json_encode($patoken);
 $ch = curl_init();
 curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 60);
 curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
 curl_setopt($ch, CURLOPT_POST, 1);
 curl_setopt($ch, CURLOPT_USERAGENT, 'SSTS Browser/1.0');
 curl_setopt($ch, CURLOPT_ENCODING, 'gzip');
 curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
 curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 1);
 
 curl_setopt($ch, CURLOPT_URL, 'http://www.scutephp.com/api.php/cc/getjson');
 curl_setopt($ch, CURLOPT_POSTFIELDS, $json_string);
 curl_setopt($ch, CURLOPT_HTTPHEADER, $header);
 $ret = curl_exec($ch);
 print_r(json_decode($ret, true));
 }
}